Optical projectors and other optical devices may utilize a laser or other relatively bright light source to project an image onto a surface. For example, some depth-sensing cameras may utilize a diffractive optical element to transform light from a laser source to project a structured light pattern on a target in the field of view of an image sensor. Variations in the structured light pattern from an expected pattern that are caused by the distance of the target from the camera may be used to determine a distance of the target from the camera.
Depth-sensing cameras and other optical systems may rely upon the location of DOEs and other optical components to remain constant for proper device performance. Therefore, in the case of a depth-sensing camera, if an optical element becomes misplaced or damaged, the reference structured light image may change compared to that expected by the image processing software. However, such an optical system fault may not be easily discernable by the camera and depth-sensing image processing software. Therefore, various faults may result.